Ameliorating effects of aged garlic extracts against Aβ-induced neurotoxicity and cognitive impairment

Abstract

BackgroundIn vitro antioxidant activities and neuron-like PC12 cell protective effects of solvent fractions from aged garlic extracts were investigated to evaluate their anti-amnesic functions. Ethyl acetate fractions of aged garlic had higher total phenolics than other fractions.MethodsAntioxidant activities of ethyl acetate fractions from aged garlic were examined using 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) diammonium salt (ABTS) and malondialdehyde (MDA) inhibitory effect using mouse whole brain homogenates. Levels of cellular oxidative stress as reactive oxygen species (ROS) accumulation were measured using 2',7'-dichlorofluorescein diacetate (DCF-DA). PC12 cell viability was investigated by 3-[4,5-dimethythiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) and lactate dehydtrogenase (LDH) assay. The learning and memory impairment in institute of cancer research (ICR) mice was induced by neurotoxic amyloid beta protein (Aβ) to investigate in vivo anti-amnesic effects of aged garlic extracts by using Y-maze and passive avoidance tests.ResultsWe discovered that ethyl acetate fractions showed the highest ABTS radical scavenging activity and MDA inhibitory effect. Intracellular ROS accumulation resulting from Aβ treatment in PC12 cells was significantly reduced when ethyl acetate fractions were presented in the medium compare to PC12 cells which was only treated with Aβ only. Ethyl acetate fractions from aged garlic extracts showed protection against Aβ-induced neurotoxicity. Pre-administration with aged garlic extracts attenuated Aβ-induced learning and memory deficits in both in vivo tests.ConclusionsOur findings suggest that aged garlic extracts with antioxidant activities may improve cognitive impairment against Aβ-induced neuronal deficit, and possess a wide range of beneficial activities for neurodegenerative disorders, notably Alzheimer's disease (AD).

Implicating the role of lycopene in restoration of mitochondrial enzymes and BDNF levels in β-amyloid induced Alzheimer׳s disease

“…Specifically, it has been shown that β-amyloid promotes oxidation in several experimental systems (Jeong et al, 2013) and conversely, pro-oxidants increase the production of β-amyloid (Tamagno et al, 2005). Thus, reducing oxidative stress through antioxidant supplementation has received considerable attention as a therapy to retard AD.…”

Black Garlic and Its Therapeutic Benefits

“…Nillert and collaborators had established a neuronal degenerative model by treatment with 1 μl of aggregated Aβ in the lateral ventricles; eventually they observed that ethanol extract-aged black garlic, a variant form of black garlic produced by aging the fresh garlic in room temperature, could ameliorate short-term recognition memory and inhibit activation of microglia as well as production of IL1β, a proinflammatory cytokine [46]. Additionally, ethyl acetate fraction of aged garlic extract protects PC12 neuron-like cells and ICR mice from neurotoxicity and amnesia induced by Aβ (25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35) [47]. Note that both aged and black garlics are rich of S-allyl-cysteine content, a stable bioactive organosulfur compound which also exerts anti-inflammatory, neuroprotective, and antioxidant effects [48].…”

Protective Effect of Hyperforin on β Amyloid Protein Induced Apoptosis in PC12 Cells and Colchicine Induced Alzheimer’s Disease: An Anti-oxidant and Anti-inflammatory Therapy

“…Afterwards, NaoH 250 μL was added in each well and after 30 min the supernatant was collected and again incubated at 37 . The microplate reader was used for estimation the LDH activity at 450 nm 20,21 .…”